"Don't modify selector in place" breaks IDs array behavior

[johnnyshields]

Re: commit https://github.com/mongoid/origin/commit/9f8c2eaabed9f4e363eb31c57ce0ee1100ce8e04 which was added in Origin v1.0.11

(Assume foo has_many bars)

   @foo.bar_ids << @bar.id
   @foo.bar.should == [@bar]   # breaks after aforementioned commit

[durran]

The fact that this was working before was an accident - the documented behaviour is to set the ids array, as so:

https://github.com/mongoid/mongoid/blob/master/lib/mongoid/relations/accessors.rb#L256

[johnnyshields]

Thanks, this makes sense!